Ford Ranger: High rpm's when cold

[Tyme2fish]

I've got a Ford Ranger 1999 V-6 5 speed. When it's real cold, my RPM's run wild. It's like the "old" days when the choke would stick. After the vehicle warms up, the RPM's return to normal.<br />This is dangerous because I can run down the highway like I have cruise control (which I don't)<br />at 50 mph. I just put it in neutral when stopped at a light,etc. <br />Any ideas on what's happening? Throttle body, etc?

 

[KRS]

Re: Ford Ranger: High rpm's when cold

holy crap! stop driving it until you figure it out man!<br /><br />i'm not your passenger, but I'm scared already.<br /><br />Hope someone has useful info for you, and not my worthless drivel.

 

[Tyme2fish]

Re: Ford Ranger: High rpm's when cold

I may have exaggerated a bit on the 50mph <br />But I do thank you for your concern. And yes, I drive another vehicle when it's cold!<br /><br />I guess you don't have that problem in Arizona!!

 

[JasonB]

Re: Ford Ranger: High rpm's when cold

My '92 3.0 Ranger 5spd did exactly the same when the idle speed sensor or solenid went out. $75 part, 3 minutes to fix. It's under the plastic cover where the throttle pull is. There's a sensor and a solenoid there. One is $25, the other is $75. Can't remember which, but I figured with my luck, the more expensive of the two went out. Bought the $75 one and problem solved. I think it was the sensor because the solenoid was still actuating the throttle causing the revving. <br /><br />I can't remember if it ever threw a check engine light or computer code, but I don't think it did.<br /><br />If it were an auto, you'd destroy it tyying to get it in/out of gear.

 

[Limited-Time]

Re: Ford Ranger: High rpm's when cold

Ya getting any warning lights or any thing? Seems as the ECM would detect an incorrect idle rpm at start up and throw an alarm. Any way I’d take it to an Advanced Auto Parts type store and have the codes read. They will generally hook ya up and read ya for free. At least they do around here. Good luck.

 

[Reel Poor]

Re: Ford Ranger: High rpm's when cold

Possible vaccum leak. Check hoses and pcv valve, sometimes the pvc valve will come apart and let way to much vaccum through.<br /><br />Possible Idle Air Control Motor (IAC). This is the most likely problem.

 

[JasonJ]

Re: Ford Ranger: High rpm's when cold

It could be the thermostat is going. If the 'stat is bad, it takes longer to warm up, so the engine will stay in open loop warm up mode, which keeps the rpms high. I just went through this with my sisters car. When the temps were down in the single digits, the thing never dropped out of its high idle and the heater was tepid at best. A new 'stat fixed that. <br /><br />I also had a vacuum line that was attached to a port on the intake manifold of my Jeep Grand Cherokee fail, and it caused the rpms to stay way up as well. Check the easy stuff first before you go buying expensive sensors...

 

[JasonB]

Re: Ford Ranger: High rpm's when cold

TTF, If you have the Haynes book for your truck, I'm vaguely remembering a way to test the sensor I mentioned with a analog multitester as I think you can set the tester to measure resistance and watch the needle to see if the sensor is working. You can also watch the throttle lever to see if the solenoid is actuating it. It's been 3 years or so and my memory is foggy. <br /><br />RP has a good thought in checking Vacuum. If your 3.0 is like mine, there is a vacuum "tree" hanging off the back of the intake that has multiple vacuum lines to it.

 

[gatorred]

Re: Ford Ranger: High rpm's when cold

try carb cleaner in fuel injector head the two valve thing then disconect battery over night it clears the computer or ecm but if sencors, got me it will still do it if gumed up it will help <br />ps i had buick crank senor ran for 20 min's then quit that was 1150 dollers later to find, tried fuel pump,fuel pump holder, fuel tank, fuel lines it was 800 dollers not any better then 200 labor that guy 150 at buick sent me to guy gas station he did it to quicker they knew him odd not show on computer either

 

[DJ]

Re: Ford Ranger: High rpm's when cold

Three possibilities or a combination of the three.<br /><br />1. Vacuum leak. However, temperature would not make a difference, unless it is at the idle air bypass valve.<br /><br />The IAB is on top of the intake manifold air horn. Remove it and clean the passages with the spray especially meant for these valves. DO NOT USE REGUALR CARB. CLEANER. Any auto parts store will have it.<br /><br />2. Gummed up idle air bypass valve.<br /><br />See #1.<br /><br />3. Sticking throttle butterflies.<br /><br />If the plate sticks slightly open (crud and dirt) The computer will try to overcompensate.<br /><br />Remove the rubber snorkel and use the same cleaner as above on the throttle plate. Pay special attention to where the plate makes contact with the housing.

 

[Tyme2fish]

Re: Ford Ranger: High rpm's when cold

Thanks to all for your suggestions. The weather has been warm lately so no problem. PS My roof only leaks when it rains.

 

[Tyme2fish]

Re: Ford Ranger: High rpm's when cold

Son-in-law fixed the problem. Dirty idle selonoid. Cleaned it up and runs fine now.

 

[LubeDude]

Re: Ford Ranger: High rpm's when cold

Originally posted by Tyme2fish:<br /> Son-in-law fixed the problem.

Remember when you thought he wasnt worth a dime and wasnt good enough for your daughter?????????<br /><br />Well, hes redeammed himself!

 

[Tyme2fish]

Re: Ford Ranger: High rpm's when cold

Remember when you thought he wasnt worth a dime and wasnt good enough for your daughter?????????<br /><br />Lubedude: Never ever thought that about him. He's always been AOK in my book.Nice Christian man, and he provides for his family.<br />I know you were just "funning" me.